Vacuum control for pulp molding machines



Jan. 9, 1962 Filed Aug. 11, 1960 D. T. DANIELE 3,016,091

VACUUM CONTROL FOR PULP MOLDING MACHINES 5 Sheets-Sheet l #IT'. .93 I vN I a w l 2 9 9 .8 l m g E; :II I I" i 5 i ll i N n o i g I i I l '1 U i1 l I i i 8 I l l g i 1 I '1 1| I I h "Tin INVENTOR Donald T. DanieleATTORNEY D. T. DANIELE VACUUM CONTROL FOR PULP MOLDING MACHINES Jan. 9,1962 I 3 Sheets-Sheet 2 Filed Aug. 11, 1960 INVENTOR Donald l1 DanieleATTORNEY Illll 8 w 5 I? -I-= w x r1.5% .=iIlli==i 8 i .n t 7 BY KARI.LJTZoc K5 Jan. 9, 1962 I D. T. DANIELE 3,016,091

VACUUM CONTROL FOR PULP MOLDING MACHINES Filed Aug. 11, 1960 3Sheets-Sheet s INVENTOR Dona Id 'IZ Daniele BY KARI. 'FZ ocKs ATTORNEYUnited States Patent 3,016,091 VACUUM CONTROL FOR PULP MOLDING MACHINESDonald T. Daniele, East Longmeadow, Mass, assignor to Diamond NationalCorporation, New York, N.Y., a

corporation of Delaware Filed Aug. 11, 1960, Ser. No. 48,886

9 Claims. (Cl. 162-391) This invention relates to vacuum controls forpulp molding machines, and more particularly to a valve for controllingthe periodic application of a vacuum to suctiontype rotary pulp moldingmachines. This application is a continuationin-part of applicationSerial No. 801,884, filed March 25, 1959, by the same inventor, nowabandoned.

In the manufacture of molded pulp articles by suctiontype rotary pulpmolding machines, a vacuum is customarily applied periodically to aseries of suction molds as they are advanced successively through a vatof pulp slurry, in which the pulp articles are formed by suctiondeposition onto the molds. Subsequently, the pulp articles are removedfrom the molds by a plurality of cooperating transfer dies, to which thevacuum is also periodically applied to hold the pulp articles thereontemporarily. These dies may transfer the articles to a conveyor leadingthrough a drying oven to a stacking and storage area. In some types ofmolding machines the transfer dies are mounted on a hollow rotatableshaft for oscillatory movement through an arc of 180 back and forthbetween an article receiving position and an article discharge position,and the vacuum is applied intermittently to the dies through the hollowshaft on which they are mounted during such oscillation. For suchpurposes, various complicated controls and complex valve structures havebeen proposed heretofore to regulate the application of the vacuumthereto.

An object of the present invention is to provide new and improved vacuumcontrols for pulp molding machines.

Another object of the invention is to provide new and improved valvesfor controlling the periodic application of vacuum to suction-typerotary pulp molding machines.

Still another object of the invention is to provide new and improvedcontrols for periodically applying pneumatic or other fluid motive powerto rotating or oscillating article carrying elements of pulp moldingmachines.

Yet another object of the invention is to provide a new and improvedvalve for controlling the periodic application of vacuum to anoscillatable transfer die.

Other objects and the nature and advantages of the instant inventionwill be apparent from the following detailed description, taken inconjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic side elevation view of one type of pulp moldingmachine in which controls embodying the present invention may beincorporated;

FIG. 2 is a fragmentary vertical section of a plurality of oscillatabletransfer dies mounted on a hollow rotatable shaft which is connected toa vacuum control device embodying the present invention;

FIG. 3 is an enlarged vertical section of the control device shown inFIG. 2, depicted in one operating position;

FIG. 4 is a view corresponding to FIG. 3, but showing the control devicein another operating position;

FIG. 5 is a transverse vertical section taken along the line 55 of FIG.3; and

FIG. 6 is a vertical section taken along the line 66 of FIG. 3.

The pulp molding machine illustrated schematically in FIG. 1 isrepresentative of one well known type of ma 3,016,091 Patented Jan. 9,1962 chine used commercially for the production of relatively simplemolded pulp articles, such as dishes, flower pots or other types ofcontainers. This machine comprises a plurality of suction molds 10mounted on hollow spokes 12 which project radially outwardly from anintermittently rotatable hollow shaft 14 adapted to advance the molds 10in a circular path successively through a vat 16 containing dilute pulpslurry. Vacuum is applied internally to the molds 10 through the spokes12 and the shaft 14 as the molds 10 advance through the pulp slurry inthe vat 16 to form molded pulp articles by suction deposition onto themolds. As the molds 10 emerge from the pulp slurry and rise upwardlythereabove, the application of the vacuum is continued to drain excessmoisture from the molded pulp articles thereon.

When the molds 10 reach the uppermost position in their circular path oftravel, the vacuum is automatically shut off and an internal blast ofcompressed air may be applied to transfer the molded pulp articles to atraveling compression and transfer die 18 suspended directly above themolds 10. The die 18 is capable of both vertical and horizontalreciprocation, and it is movable along a horizontal track 20 to carrythe molded pulp articles successively over to a position directly abovean oscillatable transfer die 22, which is adapted to invert the moldedpulp'articles and transfer them to a conveyor belt 24. The transfer die22 is mounted on a hollow rotatable shaft 26 through which vacuum isapplied intermittently to hold the pulp articles on the die 22. Thevacuum is applied as the articles are received from the die 18 and asthey are carried through an arc of 180 to an inverted position above theconveyor belt 24, and then the vacuum is automatically shut off to allowthe articles to drop onto the conveyor belt 24.

FIG. 2 shows a plurality of transverse dies 30, corresponding to the die22 of FIG. 1, mounted on a common horizontal hollow rotatable shaft 32journaled in a vertical frame 34, of which only a fragment is shown.Suitable driving means 35 is provided for turning the rotatable shaft 32alternately in opposite direction in steps of 180, thereby to oscillatethe dies 30 in the same manner as has been described for the die 22 ofFIG. 1. During this oscillatory motion a vacuum control embodying thepresent invention, indicated generally at 36, controls the periodicapplication of the vacuum to the dies 30.

The vacuum control device 36 comprises a valve head 38, which in theillustrated embodiment of the invention is annular in configuration,secured by bolts 40 to a base 42 mounted on a horizontal bracket 44projecting" laterally from the frame 34. Thus, the valve head 38 issecurely anchored against rotation with the rotatable shaft 32 on whichthe transfer dies 30 are mounted. The hollow shaft 32 is joined by akeyed union member 45 to a hollow shaft extension 46 which projectshorizontally outwardly through the frame 34 and thence through a bearing48 secured to said frame. The outer end of the hollow shaft extension 46terminates in an integral, solid, reduced portion 50, which is journaledwithin a second bearing 52 mounted on the bracket 44 at its outer end. Aported flange 54 is secured by a key 55 to the extension 46 adjacent tothe bearing 48 for rotation with the shaft 32. The flange 54 isgenerally disc-shaped in configuration, and it is provided with aninternal radial passage 56 connecting an outer port 58 with an innerport 60, which port 60 is in communication with the interior of thehollow extension 46 of the shaft 32. The thick- 3 flange 54, and havingits opposite sides engaging said head and said flange in fluid tight orvacuum tight contact therewith, yet being capable of sliding motion relative thereto.

The disc 62 is also mounted slidably for rotation on the extension 46 ofthe shaft 32 adjacent to the reduced portion 50 thereof. The outerperiphery of the disc 62 may project slightly beyond the valve head 38and the ported flange 54, and opposite sides of the disc 62 may berecessed slightly, as indicated at 64, in order to receive said head andsaid flange in fluid tight engagement.

The disc 62 is provided with a pair of ports 66 extending entirelytransversely therethrough on diametrically opposite sides thereof nearthe outer periphery of said disc. One side of the disc 62 is providedwith a pair of arcuate grooves 68, each having one end thereofcommunicating with one of the ports 66, and having its other endextending to a point adjacent to but spaced from the other port 66. Thegrooves 68 are symmetrically arranged to extend in opposite directionsfrom the two ports 66, and these grooves each traverse an arc of about150 along the periphery of the disc 62.

When the control device 36 is in the operating position in which it isdepicted in FIG. 3, one of the ports 66 in the central control disc 62connects the port 58 in the ported flange 54 with a port 70 formed inthe valve head 38, which port 70 is connected by a pipe '72 with asource of vacuum (not shown). At this time the other port 66 in the disc62 is in communication with a second port 74 formed in the opposite sideof. the valve head 38 and which is open to the atmosphere. However, atthis time the connection with the atmosphere provided by the port 74 hasno effect upon the maintenance of the vacuum within the hollow shaft 32and the transfer dies 30, because this connection is closed by the lowerportion of the flange 54. On the other hand, when the control device 36is in the operating position in which it is depicted in FIG. 4, whereinthe flange 54 has been turned 180 from the position in which it is shownin FIG. 3, while the other elements of the device 36 have been heldstationary, the hollow interior of the shaft 32 is now placed incommunication with the atmosphere by the alignment of the ports 58, 66and 74, and the connection to the source of vacuum of port 70 is shutoff by the upper portion of the flange 54.

An overrunning type one-way' clutch 76 is mounted on the integralreduced portion 50 of the shaft extension 46 for turning the controldisc 62 in one direction only during alternate rotary movements of theshaft 32. The clutch 76 may include a cylindrical inner race 78 securedby a key 80 to the reduced portion 50 of the shaft extension 46, aplurality of wedge-cam rollers 82 held in contact with the outerperiphery of the inner race 78 by a light spring 84, and an outer race86 mounted concentrically in sliding contact with the rollers 82. Theouter race 86 is secured to the control disc 62 by a plurality of bolts88 for movement therewith.

Rotary movement of the shaft 32 in one direction, in which the innerrace 78 is carried therewith due to the key 80 connecting this race withthe reduced portion 50 of the shaft extension 46, causes the wedge-camrollers 82 to turn into wedging position wherein they wedge between theinner race 78 and the outer race 86, so that these races traveltogether. Opposite rotary movement of the shaft 32 turns the rollers 82into disengaging position wherein they allow the outer race 86 to slidefreely with respect to the rollers 82, so that the inner race 78 maycontinue to turn without carrying the outer race 86 therewith.

In order to prevent the outer race 86 from moving when the cam rollers82 are in their disengaging position, a friction brake band 90 is heldin circumferential contact with a portion of the outer periphery of theouter race 86, as is best shown in FIG. 6. The brake band 90 is urgedagainst the outer race 86 by a pair of springs 92 encircling a pair ofbolts 94 mounted on the base 42 at opposite ends of the brake band 98.Due to this arrangement the brake band always remains in frictionalcontact with the outer race 86, and the frictional contact is suflicientto hold the outer race 86 stationary when the clutch 76 is disengaged,but when the clutch 76 is engaged the driving force thereof overcomesthis frictional contact to carry the outer race 86 and the control disc62 along with the shaft 32. In this manner, the rotation of the controldisc 62 is limited to turning in one direction only, in steps of 180,while the ported flange 54 turns alternately in opposite directions alsoin steps of 180 during the oscillation of the transfer dies 30.

Operation At the start of a complete operating cycle, the transfer dies30 may be in the upwardly projecting position in which they are shown inFIG. 2, wherein they are ready to receive molded pulp articlestransferred thereto from a rotary pulp molding machine, and the vacuumcontrol device 36 at this time connects said dies through the hollowrotatable shaft 32 on which they are mounted with the source of vacuum(not shown). As is best shown in FIG. 3, the vacuum connection isprovided by the alignment of the ports 58, 66 and 78, formed in theflange 5 the central control disc 62, and the valve head 38,respectively. The port 7 Q is connected by the pipe 72 with said sourceof vacuum to complete the connection. Now, the shaft 32 is turned tocarry the dies 30 through an arc of 180 to their inverted, downwardlyprojecting position where the molded pulp articles are dropped off whenthe application of the vacuum thereto is terminated. During this motionof the shaft 32 the ported flange 54 is carried therewith, but the otherelements of the control device 36 remain stationary, the control disc 62being held against rotation by the cooperation of the friction band 98with the outer race 86 of the clutch 76, which race 86 is secured to thedisc 62 by the bolts 88. The vacuum connection continues in eflfect asthe port 58 is moved away from the port 66 during the turning of theflange 54, due to the registration of the port 58 with the arcuategroove 68 formed in one face of the disc 62. This condition continueswhile the port 58 transcribes an arc of about and thereupon reaches theopposite end of the arcuate groove 68. The vacuum connection is brokenwhen the port 58 passes beyond the end of the groove 68, but the vacuummomentarily remains in effect within the hollow shaft 32 and the dies 30while the port 58 moves across the intervening flush portion of the faceof the disc 62, until the port 58 reaches the other port 66 whichcommunicates with the atmosphere. Termination of the vacuum in thismanner discharges the molded pulp articles from the transfer dies 30.

At the beginning of the second half of the operating cycle, the vacuumcontrol device 36 is in the position in which it is illustrated in FIG.4, wherein the ports 58 and 74 are aligned with each other and with oneof the ports 66 in the disc 62 to provide communication with theatmosphere. Now, as the shaft 32 is turned in the opposite direction tocarry the dies 30 through the arc of back to their original position atthe start of the operating cycle, both the flange 54 and the centralcontrol disc 62 are turned therewith. The disc 62 is moved by wedgingengagement of the rollers 82 between the inner race 78 and the outerrace 86 of the clutch 76, and such motion in this direction only ispermitted by overcoming the fractional contact between the brake band 90and the outer race 86. At the conclusion of this half of the operatingcycle, the port 58 is once again brought into alignment with the port 70in the valve head 38, thereby placing the transfer dies 30 incommunication with the source of vacuum.

Thus, in the unique valve action provided by control devices embodyingthe present invention, the disc-shaped flange 54 is turned alternatelyin opposite directions in steps of 180", while the central control disc62 is turned in one direction only in steps of 180 along with the flange54 during alternate movements thereof, and the valve head 38 remainsstationary at all times. This arrangement provides effective controlwith simplicity of structure and minimum wear of moving parts.

It is evident that the three primary control elements, which have beenillustrated and described in detail as an annular valve head 38, adisc-shaped flange 54 of unequal thickness and a central control disc62, may all be made in the form of generally symmetrical discs adaptedto co operate with each other. While a specific one-way clutch and abrake therefor have been illustrated and described, it should beunderstood that other types of one-way clutches and brakes arecontemplated as suitable for purposes of the present invention.

Although the invention has been described with particular reference tocontrolling the intermittent application of a vacuum to oscillatabletransfer dies for pulp molding machines, control devices embodying theinvention may be employed advantageously for periodically applyingpneumatic or other fluid motive power to rotating or oscillating articlecarrying elements of various type of machines.

It will be obvious to those skilled in the art that vari ous changes maybe made without departing from the spirit of the invention and thereforethe invention is not limited to What is shown in the drawings anddescribed in the specification but only as indicated in the appendedclaims.

What is claimed is:

1. In a vacuum control device for pulp molding machines and the like,wherein an oscillatable article carrying element is mounted upon ahollow rotatable shaft which turns alternately in opposite directions,the improvement comprising a first valve element secured to said shaftfor turning motion therewith and having a passage communicating with thehollow interior thereof, a second valve element mounted non-rotatablyadjacent said first valve element, said second valve element having apair of ports communicating with a source of vacuum and with theatmosphere, a third valve element mounted rotatably intermediate saidfirst and second valve elements with its opposite sides in contacttherewith, said third valve element having a plurality of passages forselectively connecting the passage in the first valve element with theports in the second valve element, and means for turning the third valveelement in one direction only with the first valve element duringalternate movements thereof, whereby said valve elements cooperate toconnect the hollow shaft with the source of vacuum intermittently.

2. The device defined by claim 1 wherein the first valve element is aported flange having a passage communicating with the hollow shaft, thesecond valve element is a valve head provided with said pair of ports,and the intermediate third valve element is a rotatable disc having apair of transverse passages extending completely through the disc forselectively connecting the passage in the flange with the pair of portsin the valve head.

3. In a vacuum control device for pulp molding machines and the like,wherein an oscillatable article carrying element is mounted upon ahollow rotatable shaft which turns alternately in opposite directions,the improvement comprising a flange secured to said shaft for turningmotion therewith and having a passage communicating with the hollowinterior thereof, a valve head mounted non-rotatably adjacent saidflange, said valve head having one port providing communication with asource of vacuum and having another port providing communication withthe atmosphere, a central control disc mounted rotatably intermediatethe flange and the valve head with its opposite sides in contacttherewith, said disc having passages for selectively connecting thepassage in the flange with the ports in the valve head, and means forturning the control disc in one direction only with the flange duringalternate movements thereof, thereby intermittently connecting thearticle carrying element With the source'of vacuum.

4. The device defined by claim 3 wherein the passages in the centralcontrol disc include a plurality of transverse ports extendingcompletely through the disc, and a plurality of arcuate grooves formedon one side of the disc and extending in opposite directions from eachof said ports to a point adjacent but spaced from another of said ports.

5. The device defined by claim 4 wherein a pair of the arcuate grooveseach traverse an arc of about along the side of the disc, and therotatable shaft together with the flange turns alternately in oppositedirections in steps of so that the passage in the flange is maintainedin communication with one of the grooves during a substantial portion ofthe movement of the flange relative to the disc.

6. In a vacuum control device for pulp molding machines and the like,wherein an oscillatable article carrying element is mounted upon ahollow rotatable shaft which turns alternately in opposite directions,the improvement comprising a generally disc-shaped flange secured tosaid shaft for turning motion therewith, said flange having a radialpassage communicating with the hollow interior of the shaft, a valvehead mounted nonrotatably adjacent said flange, said valve head havingone port communicating with a source of vacuum and having another portcommunicating with the atmosphere, a central control disc mountedrotatably intermediate the flange and the valve head with opposite sidesof the disc in fluid tight slidable contact with said flange and saidvalve head, said disc having a pair of passages in diametricallyopposite portions thereof for selectively connecting the passage in theflange with one of the two ports in the valve head, and a one-way clutchconnecting the disc with the shaft during alternate movement thereof forcausing the disc to turn in one direction only therewith, therebyintermittently connecting the article carrying element with the sourceof vacuum.

7. The device defined by claim 6 wherein the pair of passages in thecentral control disc include a pair of transverse ports extendingcompletely through the disc on diametrically opposite portions thereof,and a pair of elongated arcuate grooves formed in one side of the discand extending symmetrically in opposite directions from each of saidports to a point adjacent but spaced from the other port.

8. The device defined by claim 7 wherein the pair of arcuate grooveseach traverse an arc of about 150 along the side of the disc, and therotatable shaft together with the flange turns alternately in oppositedirection in steps of 180, so that the passage in the flange ismaintained in communication with one of the grooves during a substantialportion of the movement of the flange relative to the disc,

9. In a vacuum control device for pulp molding machines and the like,wherein an oscillatable article carrying element is mounted upon ahollow rotatable shaft which turns alternately in opposite directions insteps of 180, the improvement comprising a generally disc shaped flangesecured to said shaft for turning motion therewith, said flange having aradial passage communicating with the hollow interior of the shaft, avalve head mounted non-rotatably adjacent said flange, said valve headhaving one port communicating with a source of suction and havinganother port communicating with the atmosphere, a central control discmounted rotatably intermediate the flange and the valve head withopposite sides of the disc in fluid tight slidable contact with saidflange and said valve head, said disc having a pair of transverse portsextending completely through the disc on diametrically opposite portionsthereof for selectively connecting the passage in the flange with one ofthe two ports in the valve head, one side of said disc having a pair ofelongated arcuate grooves extending symmetrically in opposite directionsfrom each of said ports through an arc of about 150 to a point adjacentbut spaced from the other port, and a one-way clutch mounted on theshaft and adapted to turn the disc with the shaft in one direction onlyduring alternate turning movements thereof,

References Cited in the file of this patent UNITED STATES PATENTSChaplin May 23, 1916 Giorgini May 4, 1954

